function [ output ]=sigma3_cal(input)
%Environmental interference force
Tau1=0;
Tau2=0;
Tau3=0;

%Heavy vehicle
m11=646;
m22=837;
m33=155;
m23=0;
m32=0;
d11=303;
d22=425;
d33=74;
d23=0;
d32=0;

u=input(1);
v=input(2);
r=input(3);
r_d_dot=input(4);
r_d=input(5);

sigma3=(m11-m22)*u*v-d33*r-m33*r_d_dot+Tau3;
r_e=r-r_d;
output=[sigma3,r_e];